1. Field of the Invention
The present invention relates to electrical connectors and more specifically, the present invention relates to a right angle electrical connector.
2. Description of the Related Art
Electrical connectors are used to place electrical devices, such as printed circuit boards, in communication with one another. An electrical connector may be thought of as having two portions, one portion of which connects to a first electrical device and the second portion of which connects to a second electrical device to be put into communication with the first device. To connect the two devices, the two portions of the electrical connector are mated together.
Each portion of the connector includes one set of contacts or terminals adapted to be communicatively coupled to an electronic device and a second set of contacts or terminals adapted to be communicatively coupled to the other connector portion. This can be readily accomplished by designating one portion of the connector as having “male” contacts or terminals adapted to be coupled to the other connector portion's “female” contacts or terminals. Regardless of the specific design of the contacts or terminals, the two connector portions should be adapted to be easily connected and disconnected from each other to respectively electrically link and unlink the electrical devices to which they are connected.
Accordingly, each connector portion is fixedly connected to an electronic device through its remaining set of contacts or terminals. The contacts or terminals may be removably or permanently connectable to the electrical device; however, it is usually desired that the connector portion be secured to the electrical device through some physical mechanism. Typically, the connector portions are secured to electrical devices by fusing the contacts or terminals to contact pads or the like formed on the electrical device.
Recently, there has been a trend toward miniaturization of most electrical devices. As electrical devices become smaller and more complex, the electrical connectors used with these devices must also become smaller and must be able to accommodate the more complex devices. One problem with miniaturized electrical connectors arises from the increased precision of placement necessary to produce the proper positioning and connection of the connector contacts or terminals onto the device. This problem is exacerbated by the ever-increasing input/output (I/O) density requirements demanded of the progressively smaller electrical connectors by increasingly miniaturized electrical devices. With increased pin counts (e.g., greater number of terminals) in each connector, it becomes more and more difficult to maintain desired levels of co-planarity while maintaining contact of all of the terminals to a substrate or PCB.
One method of addressing the need for increased I/O density is to provide an array connector. Such an array connector can provide a high-density two-dimensional array of contacts or terminals for interfacing with an electrical device. However, array connectors present attachment difficulties regarding connection to devices (i.e., circuit boards or substrates) since most of the contacts or terminals must necessarily be positioned in the interior of the two-dimensional array area and are accordingly difficult to align upon connection, visually inspect, and/or repair.
The use of a right angle connector, as shown in FIG. 10, is known. This type of right angle surface mount connector can be used for an array connector or a backplane connector. As is seen in FIG. 10, a PCB 600 must have a plurality of thru holes 610 formed therein to accommodate tails 652a of the contacts 652 of the right angle connector 650.
The tails 652a of the contacts 652 are typically compliant pins that provide electrical connections to the printed circuit board 600. The compliant pins 652a in right angle backplane connectors adversely affect signal integrity because they require the large diameter plated thru holes 610 to be formed in the printed circuit board. These large plated thru holes 610 require large anti pads to be placed in the ground planes of the printed circuit board, which also adversely affect the signal integrity.
As can be determined from FIG. 10 (and FIG. 1 of U.S. Pat. No. 6,652,318), when the right angle connector is assembled to the PCB, significant forces are required to insert the compliant pins 652 into the plated holes 610, and the other ends 652b of the contacts 652 must be attached to another PCB or electrical device as seen FIG. 1 of U.S. Pat. No. 6,652,318, which causes non-symmetric forces.
When the compliant pins 652a are inserted into the plated thru holes 610, many problems may occur. In many cases, non-symmetrical forces are applied when mating and unmating the right angle surface mount connector 650.
Another problem with the right angle connector shown in FIG. 10 is that the path lengths of the contacts 652 vary substantially from contact to contact. These different path lengths cause problems with skew. In the present application, “skew” means that signals which are sent at the same time arrive at the receiver at different times. In addition, the different path lengths may prevent uniform impedances for the contacts 652.